Mechanical linkage



May 2, 1950 A. c. HovEN ET AL 2,506,151

MECHANICAL LINKAGE Filed Nov. 5, 194'? 6 Sheets-Sheet 1 me/M044 Alfred C. Hoen May 2, 1950 A. c. HovEN ET Al.y 2,506,151

MECHANICAL LINKAGE Filed Nqv. 5, 1947 e sheets-sheet 2 vwa/wm Alfred C. Holen JMQPM www May 2, 1950 A. c. HovEN ET Al.- 2,505,151

MECHANICAL LlNKAGE Filed Nw. 5, 1947 A s sheets-sheet 5 wgfmwm A. C. HOVEN ET AL May 2, 195o MECHANICAL LINKAGE 6 Sheets-Sheet I Filed Nov. 5, 1947 grwQ/wfo'td, Alfred C. Hoden ,Ver ZMedmavla attori/Maj May 2, 1950 A. c. HovEN E-r AL 2,506,151

MECHANICAL LINKAGE Filed NQV. 5, 1947 6 Sheets-Sheet 5 .lfred C. Hoden anim/MW May 2, 1950 A. c. HovEN ET Al. 2,506,151

MECHANICAL LINKAGE Filed Nov. 5, 1947 Sheets-Sheet 6 Patented May 2, 1950 MECHANICAL LINKAGE Alfred C. Hoven, Walter E. Nordmark, and Wil.- l

. liam S. Lindberg, Grand Rapids, Michl, 'assignors to American Seating Company," Grand Rapids, Mich., a corporation of New Jersey Application November 5, l9 4 7, Serial N0-.*784,182 'I The present invention relates to mechanical linkage whereby a member may be movably mounted on a iixed support therefor, and more particularly to provide such a mechanical linkage which is especially well adapted for use in chairs or the like having horizontally retractable seats and backs or vertically adjustable supporting pedestals, and this application is a continuationin-part from our co-pending application for patent on Chair, Serial No. 767,992, led August 11, 19.47. The specific combination of the mechanical linkage herein claimed with a retracting type theater chair, as disclosed in Figures 4 7 'of the drawings herein, 'is claimed in our co-pending divisional application Serial No. 148,228, led March 7, 195-0.

The Vprimary objects of the invention are to provide a novel arrangement of pivotally connected links which, when mounted on a xed supporting member, functions to support a mov- '6 olaims. (ci. 74--103lv a mechanical link-ageadapted Vfor general appliunit is desirably mounted for vertical adjustment able member for guided movement relative to the fixed supporting member in ian approximately straight path of movement; to provide such an arrangement of pivotally connected links which functions as stated irrespective of the direction ofthe said straight path of movement, and which may therefore be mounted at any selected .angle onthe 'fixed supporting member so as to support the movable member for guided movement in 'an approximately straight path in any direction desired; to provide such a mechanical linkage which is adapted to so support a movable member Ifor movement in an approximately straight path and which also maintains the supported movable member at substantially the same predetermined angle of inclination during its movement relative to the fixed member; to provide a chaifstructure of the retracting type for. use in theaters or thelike, in which chair structure suchv a mechanical linkage is employed, in this application .of which the linkage is mounted on the supporting standards for the chair and in turn provides a mounting for a chair seat in such a manner that the seat is movable rearwardly-downwardly and forwardly-upvvardly` in .rearwardly and forwardly with the seat and is angularly tilted during such movements so that when in its forward position the back is rearwardly-upwardly inclined and. in its rearwardposition 4said back is substantially vertical to provide .Such

.an approximately straight path and is mainrelative to a iixedsupporting base therefor; and in general to provide such aA mechanical linkage which is simple and rugged in construction and reasonably economical in manufacture.

These obj ectsand such other objects of the invention as will hereinafter. become apparent are attained by, and the invention nds preferable embodiments in, the devices .and structures hereinafter particularly described and illustrated in the` accompanying-drawings, wherein:

Figure 1 vis' a view, partially diagrammatic, of an arrangement of mechanical linkage, supporting means therefor, and other means supported thereby; l

Figure 2 is a fragmentary view illustrating a variation or modicationrof the linkage shown inFigurel;

Figure 3 is a view, partially diagrammatic, of another variation or modication of the mechanical linkage shownin Figure l;

Figure 4 is a side elevational view of a theater or auditorium chair of the retracting type, employing the novellinkage of the present invention,k the chair being here shown with the seat and back thereof .in .their forward or unstretched positions; i.

Figure 5 is a `fragmentary front elevational view of the chair shownpartly in section taken o n the line 5- 5v of Figure`4; j

Figure 6 is an enlarg ed, fragmentary sectional view of partscithe chair, takenon line'-S of Figure 4; i.

Figure 7 is a side.. ele vational view of the chair shown in Figure 4 Withtheseat and back thereof in their rearward, retracted, positions;

Figure 8 is a side elevational view, shown partly in section taken on line 8 8 of Figure 10, of a vertically adjustablechair of the general type used as operators seats in motor buses or other vehicles, the seat here-,being shown in an elevated position relative to, tsnxed supporting base; Figure gis ayiewjsimilar to Figure 8 and show ing the seat in a lovvred'position relative to its fixed supporting base;` and v l Figure lil'v 1SA a fragmentarysectional view o f tbesametakenhn line lll-lll of Figure 8.

Referring {n ow in. detail to Figure 1 of the drawings, themechanial linkage there shown is mounted on a xed supporting member indicated by two fragments thereof both designated FI and F2, it being understood that said fragments are iixed relative to each other. The linkage supports a movable member designated M for reciprocable movement in an approximately straight pathindicated by the .dottedzline designated P extending between stations designated SI and S2. A iirst or opstanding link designated II has its lower end pivotally connected to the xed supporting member at F near station SI. 'A second or supporting link I2 of substantially the same effective length as thedirstlink .II has its upper end pivotally connected-:tothe upper, 'free end of the first link II and hasits Llower end pivotally connected to the movable member M. A third or depending link If3`-has its upper end pivotally connected to the iixed supporting member at F2, near the travel path of the pivotal connection between .the iirst and second links. A fourth or'guide link ,f4 has `one 'en'd thereof pivotallyconnected to tire lowerjfree end of the third or 'depending linkk I3.and hasits other end pivotally connected vto the second link i2 and as here shown at the lattersfpoint vof pivotalconnectionto the movable'member M. A fth or connecting link I5 'has'its'opposite Yends pivotally connected'to thefiirst and third links I l and I3 respectively, atpointsxdividing these links in the followingpreferredproportiom The ratio .of the third links entirelength A to that portionB thereofwhich lies between its conneotionsto the fth link and the fixed member, is approximately double the Aratio of the first links entirelength Cto 'that portion D .thereofwhich'lies between its connections to the 'fth link and the fixed member. In equation form this relationship is expressed as follows:

andthe lengths mayfor example be as follows: A=7.1/2 inches, B=211 inches, C=10.inches, and D=6.inches.

vIt will be seen'thatinthe above arrangement, the lower end of the third link I3 is caused to move farther and fasterthan the upper end of the'nrst' link I I, and if the,preferred proportions given in the above .equation are adheredto, the thirdlinks lower end travels exactly twice as far and twice as fast as the'flrst links upper end. Thus as the upper ends of the iirst and second links I! Aandii! move to Vthe right (as viewed in Figure'l) through the positional-6 indicated on their arc of travel showrhtheends of the fifth or connecting link I.5,also move to the right through corresponding positions l-6 indicated .on their arcs of travel shown-and the lower end of the .third link I 3 and thaten'd ofthe fourth or guide link 'I4 to which` the .link [31s connected are Acaused to move twice. .asjiar through positions 1-6 indicatedon theirvarcof travel than do ,the 'upper ends of the firstand second links II and .I.2,.on.their.arc.. Theother end oflink le (the right end. as. seenin IE'igurel) being connected to .thelowerendnf'link.l2said.lower end of link I2 is likewise urged toward movement twice as farand Vtwice aszfastastheupper endof said link i12. This is impossible-`however because such movement of the link I2 would ,tend to compress it during the first phase oi themovement and to extendit during thei.last phase of said move ment,D and asa resultthe' link I4 is ,constrained `,to -change its angu1arity-relative l.to .the Hlink L it.

The angle between these 'links I3 and 'I4 thus decreases during the iirst phase of the movement and increases during the last phase of said movement. As a result, the lower end of the second or supporting link I2 is constrained to movement in an approximately straight path as indicated by the dotted line P. Movement of the lower, end fof ylink I2 in the opposite direction is likewise constrained 'to said approximately straight path. It will thus be seen that between the stations SI and S2 the movable member M can vonlytrrrove in an approximately straight path relative to the xed supporting member.

In Figure lxthe movable member M, although it travels in an approximately straight path as shown, isree to rotate about its pivotal connection to the lower end of link I'2. In Figure 2, the movable member'M2 has its rearward arm 26 pivotallyconnected to the lower end of link 22, which corresponds to the link I2 in Figure l and has an approximately straight path of movement as indicated by thedottedline P2. The-forward arm :2i of the'movable'member M2 `has a sleeve 28 slidably mounted 'ona Vrod-29 secured'as by screws'to lugs on ythe fixed supporting member shown fragmentarily atv F3 'and F5. Thusthe movable member M2 is'mounted'onthe iixed supporting member Afor;movement in an Aapproximately straight path and isL also maintainedat substantially the same .predetermined angle of inclination during its movement relative tothe iixed supporting member. In this modification shown inFigure 2, the movable member Mz'is connected to the link 22' at va pointbelowthe pivotal .connection between the links`2'2 andfz, instead of as shown in Figure'l,butthemodeoi operation is. substantially the same. This modificationshown in Figure 2 issimilar to the disclosure in our above identified application o'f which thisapplication is a continuation-impart.

InFigure 3, links 3l, 32, 33, 34 and'35 correspond .to and operate the Same as links `I I, I'2, I3, i4 and I5 respectively inFigure 1. yln't'his modicationshown .in'Figure 3, the upper end of link `3| is extendedangularly beyond its pivotalconnection to the upper end of link 32,and a sixth link 3E is pivotally connected to'the extension 31 oi the link 3i and depends Atherefrom. The forward portion of the'movable member M3 is pivotally connected to'the'lower end of the sixth link 36, said pivotal connection being in substantial' alignment with thepivotal lconnection of the movable memberM'tothe lower end oi'link 32 and with the pivotal connection of the link 3| to the fixed supporting'member F5. Thev rearward endcf the movable member M3 is guided in an approximately'straightgpath P3 identical to'thepath P of Figure 1 and shown in dotted line, while theforwardend of themovable member M3 is guidedin a curved path P4 shown in, broken line, the curvature of saidpath 'P4 being so slight that thejpath P4 is roughly coincident with and an extension of thepathfPB. The movable member M3 is thus mounted solely by mechanical linkage ion the fixedfsupporting member'F, F5, forl movement in an "approxi-- mately straight path 'and'is also'maintained at substantially `the same predetermined "angle `of inclination during its movementrelativeto the fixed eupportingmember.

The retracting-.type Atheater chair sho-wn in 'Figures V4-6 employs linkage identical 'to that shown in. Figure 3 .for mountinga chair'seatli and ,chair back '39 .on.spaced, upright. standards 4,2 which form the "xed supportingtiramefor the chair and which correspondto'the xed'support'- 5 ing member F5, F6 of Figure 3. The mountings at opposite sides of the chair are preferably identical. Upstanding links 4|, rear supporting links 42, depending links 43, guide links 44 and connecting links 45 correspond to and operate the same as links |2, |3, i4 and |5 respectively of Figure 1 and the same as links 3|, 32, 33, 34 and 35 respectively of Figure 3. Front supporting links 46 and seat carriers 41 correspond to and operate the saine as link 36 and movable member M3 respectively of Figure 3. The chair seat 38 is mounted on the seat carriers 41 as by means of hinge members 48 secured to the seat carriers by screws 49 and having hinge pins 5l! on which the seat is mounted turnably to raised and lowered positions. If d-esired, this hinge structure may include spring means (not shown) for normally maintaining the seat in a raised position.

The chair back 39 is mounted upon the rear supporting links 42 and is movable therewith, being secured thereto at the pivotal connections 5| between the rear supporting links 42 and the upstanding links 4|, and also being secured thereto by means of rivets 52.

- It will be seen that as the chair is retracted by an occupant thereof in order to permit others to pass in front of him, the seat 38 moves rearwardly in a substantially straight downwardlyinclined path and that it is maintained at substantially the same predetermined angle of inclination, while the back 39 moves rearwardly and tilts from its rearwardly-upwardly inclined po` sition shown in Figure 1 to its substantially'vertical position shown in Figure 3. Rearward movement of the seat and the back is stopped by contact of the upper ends of the links 4| with stops 53 on the standards fill, while forward movement of the seat and the back is stopped by contact of the seat carriers with stops 54 on the standards. It will be apparent that many other means for stopping these forward and rearward movements might be contrived and such means, or the stops 53 and 54 shown, may if desired be equipped with cushioning and silencing rubber bumpers (not shown). Also not shown in the drawings is means for shielding the linkage from the chair occupant, but a convenient method of accomplishing this is to extend the side portions 55 of the sheet metal back forwardly and flange them outwardly to form housings for the mechanisms.

The retracting chair described above is especially well adapted4 for installation in either straight rows of chairs or in curved rows wherein the common supports for adjoining chairs, or middle standards as they are called, converge slightly inwardly toward the front, the long links 4|, 42, 43 and 46 providing the necessary ilexibility for such installation in curved rows. This flexibility is also useful in compensating for inaccuracies in the placement of the standards. In order to prevent undersiable side play in the s-eat and back, there is preferably provided a guide at one side or if desired at both sides of the chair. The guide shown comprises an extension .f

A56 on the seat carrier 41 which projects downwardly, then outwardly, and then upwardly into an inverted U-shaped channel or guideway 51 secured to the adjacent standard 40 at the front and rear as by rivets 58. The portion of the seat carriers extension 56 which extends upwardly into the guideway 51 may desirably have oppositely stamped semi-spherical embossings 59 which insure a smooth bearing of `the guide against the side walls of the lguid'ew'ay. 51; with a minimum of friction, and a lubricant may if l serve as guides alone.

6. desired be applied to the inside of the guidef way. It will be particularly noted that the guide and guideway here described bear none of the' weight of the chair or the occupant thereof, but The weight of the chair seat and back and of the occupant thereof aresupported entirely by the mechanical linkage mounted on the standards and hereinbefore described.

Figures 8-10 disclose a chair of the verticallyadjustable type adapted for installation in motor busses or other vehicles for occupancy by the drivers thereof. The chair generally comprises a fixed supporting member or base 6D upon which is mounted a mechanical linkage comprising links 6|, B2, 63, 64, 65 and 66 which correspond to and operate the same as the links 3|, 32, 33, 34,35 and- 36 respectively of Figure 3, except that the linkage here shown provides a vertical movement in a substantially straight pathvfor a movable member or bracket 61 mounted on the rearward ends of links 62 and 66. A chair frame 68 is mounted on the bracket 61 and carries a chair seat 69 and back 1i). In this application of the invention, the duplicate mechanical linkages at opposite sides of the chair are connected by a web' 1| secured to or integral with the pair of links 6|' and a web 12 secured to or integral with the links. 66, and this arrangement lends rigidity to thel structure. A strong tension spring 13 normally urges the bracket 61 and the chair mountedV thereon in an upwardly direction to facilitate vertical adjustment of the chair Without the necessity of lifting these parts. A foot pedal 14 pivotally mounted on the base 60 may be depressed as indicated by the dotted lines of Figure 8 by the chair occupant, thus disengaging detents 15 from racks 16 on the forward end portions of links 6| and permitting the chair to descend under the weight of the occupant. The occupant may then by shifting his weight adjust the chair to the desired height and release the foot pedal 14, whereupon a pair of compression springs 11 return the detents 15 into engagement with the racks 16 and the chair is thus secured in vertically adjusted position. It will thus be seen that the present invention provides a novel mechanical linkage which is adaptable to structures wherein a movable member is mounted on a xed supporting member therefor in such a manner that the movable member is guided in a preselected substantially straight path of movement while at the same time said movable member is maintained at substantially the same predetermined angle of inclination relative to the fixed supporting member; that a theater chair of the retracting typeis provided which is smooth in operation, flexible 'to meet varying conditions of installation, sturdy in construction and attractive in appearance; and that a chair of the vertically adjustable type is provided which is smooth in operation, sturdy in construction and reasonably economical in manufacture.

The invention being-intended to be pointed out inthe claims, it is not to be limited to or lby details :of construction of the particular embodiments thereof shown in the accompanying drawings or hereinbefore described.

We claim: l. Mechanical means for mounting a movable member on a xedsupporting member therefor in' such a manner that said movable member is guided in an approximately straight path 'of movement between predetermined first and atgaipointj nearl thetravet path second statlonfpoints on the fixed supporting member; said" means comprising: a first link having one fend thereof a pivotally connected to the xedmember 'at theV first station point thereon and extending Ytherefrom at an acuteengle to said path of movement; a second link .of the same flength yas'the rst link having one end thereof Lpivotally connected to the free end of the first link and the other end thereof conneotedito the movable: memberzand movable. along saidfpath of movement between the firstand second station points on `the fixedr member; v-a third` link: having `one end thereof 'pivotallv con nected `Ito :the fixedfmemberf ati-a point. near the travel-.path ofthe-pivotal connection between the .flrstaandsecond links and:having its other ndswingable in an arcfini proximityr tothe path ofimovement ,betweenlsaid first and second stations; `a fourth link .having one Y end ,thereof pivotallyrconnected "'to' the: free end of `the third link .'anditscother end connected to tbe-second link Anear theY latters connectionV to the `movable memberyand, aVfth-link having one-end thereof pivotally `connected to the first link and the otherendthereof pivotallylconnected to the third link, theratio ofthe third links 'entirelength to that'zportion thereof fwhich i liesbetween f its A conneotionsto theflifth link and the fixed .member beingapproximately; double y the` ratio ofv the first links'entire length toI that portion thereof which lies betweenfits connectionstothe fifth link and theifixedl member.

52, Mechanicalimeansr for mounting-1a movable memberI on :a fixed supporting member therefor in `such 'a r mannerV that said movable member. is guided 'in `ian amaroximately straight path of movement -ibetween predetermined firstand secondstation points onthe fixed supportingimember, asaid .means :comprising: firstlink having one end thereof `pivot-ally. connected -V to .the fixed memberlat/the first stationzpoint thereon and extending'therefrom -at anacutefangle to said path of mcvement;;asecond link ofthe same length as the first link having .one end'thereof pivotally connecteclrto the freezend of theflrstlinkvand the other end thereof connected to the movable memberfandimovable along said path vofmovement. :between the firstf and second station points on the ,fixed member; 1a:` third link. havingl one. end thereof 2 pivotally connected l to the.V fixed member of thepivotalconnection .between :the first and second vlinks and having its other-fend swingablev in an arc in proximityf tothe .pathofv movement between 'said first amr-second' stations a fourth linkhaving-'one end thereofpivotally'- connected to the freeeend of the thirdylinka-andits other-end. connected tothe sec- Ondlink; near .the latters connection to the movable :'membei; and a fifth linkhaving one end thereofpivotally connected to the firstlinkand theiotherlend ,thereopivotally connected to the thirdilinksa-id pivotal connections `of the-fifth linkto the' first andrthird links being such that the free end of the third link travels approximately Atvv-icefasfarfas-theiree-end of ythefirstlink.

LMechanical means V- for mounting l a..movable member onaxed supportingmember therefor .in :such a .manner .that said. movable member is guided in an approximately straight :path of movement between predetermined `first and second station points on the fixed supporting member, ,saidmeanscomprising: ,a flrst'link having ponend .thereof,pvoially'connectedy to the fixed member at. ,theirststation point thereon and'ex- Vtt'eiicling:therefromat..an acute angleto saidpath of movement; .-a second link of the. samelength as the. first link having one end thereoflpivotally connected to the freeend of the first link and the other'end thereof connected to the movable member and movable along said path of movement between the first and second station points on the fixed member; a third link having one end thereof pivotally connected to the fixed member at-a point near the travel path of the pivotal connection between the first and second links and having its other end swingable in an arc in proximity to the path of movement between said first and second stations; a fourth link having one end thereof pivotallyv connected to the free end ofthe third link and its otherend connected to thefsec.- ond linkA near the latters connection to the movable member; and a fifth link having one end thereof pivotally connected to-the first linkand the other end thereof pivotally connected tothe third link, said'pivotal connections of thellfth link to the firstland-third links being such that the freeend ofthe third link travels farther than the freeend of the first link.

Ll. Mechanical means for mounting a movable member on a fixed supporting member therefor in such almanner that said movable member' is guided in an approximately straight path of movement between predetermined first and second station points on the fixed supporting member, said means comprising: a first link having one end thereof pivotally connected to the fixed member near the first station point thereon'fand extending therefrom atan acute angle to said path Vof movement; a second link of substantially the same length asv the first link having one-end thereof pivotally connected to the free end of the first Vlinkand the other end thereofv connected to the movable member and movable along said path of movement between the first and second station'points on the xed member; a third link havingone end thereof pivotally connected to the fixed member at a point near the travel path .of the pivotal connection between the first and sec ond links andhaving its other end swingable in an arciin proximity to the path of movement be* tween said first and second stations; a fourth link having one end thereof pivotally connectedto the free end of the third link and its other end -connected tothe second link near the latters connection tothe movable member; and a fifth link having one end thereof pivotally connected to the first link and the other end thereof pivotally connected to the third link, said pivotal connections of the fifth link to the first and third links being such that the free end of the third link travels farther than the free end of the first link.

5."Linkage mounted on a fixed member at'two spaced points, comprising: a first link pivotally connected to the fixed member at the first of said points and having its free end swingable in proximity to the second of said points; a second link pivotally connected to the free end of the rst link and having its free end movable in an approximately straight path intersecting the first of said pointsya third link pivotally connected to the'second of said points and having its free .end swingable in an aro having its ends. near the ends of said rapproximately straight path; a fourth,

link connecting the free ends of the second and third links; and a fth link connecting the first and'third links so as to accelerate the movement Vof the third links'free end relative tothe movement ofthe firstlinks freeend thus constrain ing-the movement ofthe connection betweenthe 9 second and fourth links to said approximately straight path.

6. Mechanical means for mounting a movable member on a fixed supporting member therefor in such a manner that said movable member is guided in an approximately straight path of movement between predetermined rst and second station points on the fixed supporting member, said means comprising: a first link having one end thereof pivotally connected to the fixed member at the first station point thereon and eX- tending therefrom at an acute angle to said path of movement; a second link of the samelength as the first link having one end thereof pivotally connected to the free end of the first link and the other end thereof connected to the movable member and movable along said path of movement between the first and second station points on the fixed member; a third link having one end thereof pvotally connected to the fixed member at a point near the travel path of the pivotal connection between the rst and second links and having its other end swingable in an arc in proximity to the path of movement between said rst and second stations; a fourth link having one end thereof pivotally connected to the free end of the lil third link and its other end connected to the second link near the latters connection to the movable member; a fth link having one end thereof pivotally connected to the first link and the other end thereof pivotally connected to the third link, said pivotal connections of the fifth link to the `rst and third links being such that the free end of the third link travels farther than the free end of the rst link; and a sixth link having one end thereof pivotally connected to the first link near its free end and having the other end thereof connected to the movable member at a point spaced from the vconnection between the movable member and the second link.

ALFRED C. HOVEN.

WALTER E. NORDMARK.

WILLIAM S. LINDBERG.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,877,769 Knapp Sept. 20, 1932 2,365 570 Lee Dec. 19, 1944 

